DESCRIPTION (provided by investigator): While considerable progress has been made in reducing cancer mortality, this has come at some cost in terms of side effects and late effects experienced by cancer survivors. One of the more serious and distressing late effects is chemotherapy-induced heart failure. Exercise training has been found to be beneficial for non-cancer patients with heart failure, as well as for cancer survivors without heart failure, but it has not been tested in cancer survivors with chemotherapy-induced heart failure. We propose to test the feasibility of an exercise intervention for survivors with heart failure due primarily to toxicity caused by chemotherapy. Additionally, we will investigate the effect of the lifestyle intervention on primary outcomes (cardiorespiratory fitness, heart failure symptoms, heart failure disease progression), secondary outcomes (physical functioning, role functioning, health care utilization), adherence to behaviors (exercise, sodium intake), and behavioral mediators (exercise self-efficacy, psychological distress). Because this is a pilot study, data will be used to develop effect size and variance estimates to be used in planning a larger randomized trial. Finally, we will explore Social Cognitive Theory-based predictors of adherence to exercise recommendations, testing the psychometric characteristics of our measures and exploring correlations consistent with our conceptual model. Participants will be recruited from the M. D. Anderson cardiology clinic. The baseline assessment will consist of cardiac biomarkers and echocardiogram;a cardiorespiratory fitness test;symptom, quality of life, and behavioral determinant questionnaires;and assessment of physical activity. After baseline, 80 patients will be assigned using minimization to receive either the 16 week Take Heart lifestyle intervention or usual care. Patients in the Take Heart intervention arm will attend supervised and monitored exercise sessions in M. D. Anderson's Behavioral Research and Treatment Center. The intensity and duration of their sessions will be individualized based on their initial fitness test, comorbid conditions, and symptoms during exercise. The goal will be for patients to work up to at least 30 minutes of exercise 3 times a week at 60-70 percent or heart rate reserve. The exercise will proceed from monitored and supervised to less supervised exercise over the course of the 16 week intervention. Analysis will include an evaluation of the feasibility in terms of recruitment and retention rates, participant safety, intervention session adherence, contamination between study arms, and participant satisfaction. We will also develop estimates of the effect sizes to use in planning larger studies. If the data collected in this pilot study indicates a larger randomized study of an exercise intervention would be feasible in this population, we plan to prepare an NIH grant application to provide funding for such a study. PUBLIC HEALTH RELEVANCE: The long term goal of this research is to provide information about whether exercise training can help cancer survivors with heart failure decrease their symptoms, improve functioning, and return as fully as possible to their normal daily activities. If effective, an exercise intervention could provide a useful management tool that is low risk, does not interfere with cancer treatment, and may benefit the cancer survivor in multiple ways, e.g., improved QOL, and the reduced risk of recurrence. Furthermore, an effective intervention for heart failure may help survivors tolerate higher, more therapeutic doses of treatment or enable them to be re-treated with effective but cardiotoxic drugs should they experience a recurrence.